private Expression GetCaseWhenExpression(Expression parent)
{
CaseWhenExpression result = new CaseWhenExpression(parent);
ParseCaseExpression(result);
return(result);
}
public void Can_Read_Case_When_Expression()
{
// setup
var tokenizer = NewTokenizer(@"
CASE
WHEN A.Field1 < 1 THEN 'Y'
WHEN A.Field2 >= 2 + A.Field3 THEN 15 / (A.Field4 * 2)
ELSE
'U'
END
"
);
tokenizer.ReadNextToken();
ExpressionParser parser = new ExpressionParser(tokenizer);
// exercise
Expression expression = parser.Execute();
// verify
Assert.IsNotNull(expression);
Assert.IsTrue(expression is CaseWhenExpression);
CaseWhenExpression caseWhen = (CaseWhenExpression)expression;
Assert.AreEqual(2, caseWhen.Cases.Count);
Assert.AreEqual("A.Field1 < 1", caseWhen.Cases[0].When.Value);
Assert.AreEqual("'Y'", caseWhen.Cases[0].Then.Value);
Assert.AreEqual("A.Field2 >= 2 + A.Field3", caseWhen.Cases[1].When.Value);
Assert.AreEqual("15 / (A.Field4 * 2)", caseWhen.Cases[1].Then.Value);
Assert.AreEqual("'U'", caseWhen.Else.Value);
}
